Thermostat



FIG. 1 is a front and left side perspective view of the thermostat;

FIG. 2 is a front elevation view of the thermostat thereof; and,

FIG. 3 is a right elevation view of the thermostat thereof, the opposite side being a mirror image thereof.

The views of the thermostat not shown form no part of the claimed design. 

The ornamental design for a thermostat, as shown and described. 